What do these circuits have to do with the SRPP? Admittedly, at first glance very little. But if we start with these circuits and then add some SRPP attributes to the circuits, i.e. by subtracting components, we might get something much simpler, but not too much worse in performance. A good starting point might be to eliminate the bootstrap capacitor. 

     This change saved us not only the cost of the bootstrap capacitor, but added the cost of an additional coupling capacitor. This capacitor could be eliminated as well, but at the price of greatly reduced plate resistor values, which would greatly reduce the open-loop gain.
    Switching the output to the other input tube's plate circuit converts the output stage to a cathode follower based one, which eliminates the need for a feedback loop, as the output stage's output impedance would be sufficiently low for most applications, such as line amplifier or 300-ohm headphone amplifier. Still, the gain would be about unity, limiting this approach's appeal.
    Of course, the top tube can be capacitor coupled just as easily. The AC coupling would allow larger valued plate resistors, with the resulting benefits (such as increasing the gain from less than unity). In fact, since we have removed the global feedback loop, the coupling capacitor and its biasing resistors would help lock in place the output stage's DC operating points better than the DC coupled version could.

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